Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 25
Filter
1.
J Antimicrob Chemother ; 57(5): 955-8, 2006 May.
Article in English | MEDLINE | ID: mdl-16554337

ABSTRACT

OBJECTIVES: Urinary tract infections (UTIs) are common bacterial infections encountered in general practice. For the optimal treatment the general practitioner (GP) should rely on the results of diagnostic tests and recent antimicrobial susceptibility of uropathogens. PATIENTS AND METHODS: In total 1993 female patients (11-70 years) with complaints of an acute uncomplicated UTI were included. The performance characteristics of the diagnostic tests used were determined and compared with the antibiotic prescription rate. The antibiotic therapy (agent and duration), the uropathogens and the antibiotic susceptibility of Escherichia coli were determined for each age group. RESULTS: The positive predictive value (PPV) (96%) and the specificity (94%) of the nitrite test were high for all samples. A negative nitrite with a positive leucocyte-esterase (LE) test showed a high PPV (79%) and sensitivity (82%). When both nitrite and LE tests were negative approximately 50% of the samples were culture positive. Of the patients, 94% of those with a positive nitrite test and 71% of those with a negative nitrite and positive LE test were prescribed antibiotics, mostly nitrofurantoin and trimethoprim. Nitrofurantoin prescriptions decreased and those of fluoroquinolones increased with increasing age. Nitrofurantoin was equally prescribed for 3-7 days in all patients. Trimethoprim was mostly prescribed for 3 days in patients aged 21-50 years and for 5 days in the other patients. E. coli, the uropathogen mostly isolated, decreased in frequency with increasing age. Proteus mirabilis was found more in the oldest patients and Staphylococcus saprophyticus in the younger patients. The antimicrobial susceptibility of E. coli was not age related. The lowest percentages were found for amoxicillin (67%) and trimethoprim (77%). Fluoroquinolone resistance was emerging in the older patients. CONCLUSIONS: For female patients with symptoms of an acute uncomplicated UTI a positive nitrite test or a negative nitrite test with a positive LE test confirmed UTI whereas a negative nitrite together with a negative LE test did not rule out infection. For empirical treatment GPs should take into account the changing aetiology with increasing age. Prudent use of antibiotics in general and more specifically fluoroquinolones remains recommended. As trimethoprim resistance reached 20% it might be advisable to no longer use it as therapy of first choice for acute uncomplicated UTIs in The Netherlands.


Subject(s)
Urinalysis/methods , Urinary Tract Infections/microbiology , Urine/microbiology , Adolescent , Adult , Aged , Anti-Infective Agents, Urinary/pharmacology , Child , Colony Count, Microbial , Female , Humans , Microbial Sensitivity Tests , Middle Aged , Netherlands , Practice Patterns, Physicians' , Urinary Tract Infections/drug therapy , Urinary Tract Infections/urine
2.
Int J Antimicrob Agents ; 27(3): 236-41, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16473503

ABSTRACT

A population-based study was conducted among women over the age of 70 years with complaints of uncomplicated urinary tract infections (UTIs). The positive predictive value of the nitrite test alone or in combination with the leukocyte esterase test ranged between 83% and 99%. The nitrofurantoin prescription rate decreased whereas fluoroquinolone and amoxicillin/clavulanic acid prescriptions increased with increasing age. The aetiology of infection was age-dependent. Escherichia coli was the most commonly isolated uropathogen, followed by Proteus mirabilis and Klebsiella pneumoniae. For these uropathogens, the lowest susceptibility percentages were found for amoxicillin, trimethoprim and co-trimoxazole. As trimethoprim susceptibility reached approximately 75%, it may be advisable not to use this as a first-choice agent in the treatment of uncomplicated UTIs in the elderly.


Subject(s)
Anti-Infective Agents/therapeutic use , Bacteria/drug effects , Urinary Tract Infections/microbiology , Aged , Aged, 80 and over , Anti-Infective Agents/administration & dosage , Anti-Infective Agents/pharmacokinetics , Bacteria/isolation & purification , Drug Resistance, Bacterial , Female , Humans , Microbial Sensitivity Tests , Population Surveillance , Urinary Tract Infections/diagnosis , Urinary Tract Infections/drug therapy , Urine/microbiology
3.
J Neurol Neurosurg Psychiatry ; 75(8): 1175-7, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15258225

ABSTRACT

OBJECTIVES: To assess psychopathological symptoms and history of childhood trauma in patients with newly developed psychogenic seizures. METHODS: Using validated scales, 178 patients from the general population diagnosed with newly developed seizures were assessed, at a point in time when the nature of their seizures was yet unknown to either doctors or patients. After standardised neurological examination, 138 patients were diagnosed with non-psychogenic seizures (NPS), while 40 patients were found to have psychogenic seizures (PS). To evaluate possible differences between the genders and the diagnostic groups, univariate analyses of variance were done. RESULTS: PS patients reported significantly more comorbid psychopathological complaints, dissociative experiences, anxiety, and self-reported childhood trauma than NPS patients. In addition, PS patients had lower quality of life ratings than NPS patients. These effects were not modulated by gender. CONCLUSIONS: The results of the present study indicate that patients with newly developed PS constitute a group with complex psychopathological features that warrant early detection and treatment.


Subject(s)
Mental Disorders/complications , Seizures/etiology , Seizures/psychology , Wounds and Injuries/psychology , Adolescent , Adult , Comorbidity , Female , Humans , Male , Middle Aged , Neurologic Examination , Prospective Studies , Quality of Life
4.
Seizure ; 6(4): 311-6, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9304723

ABSTRACT

Gender-related differences for disorders of consciousness other than true epilepsy usually point to a larger number of women suffering especially from non-epileptic attacks or pseudoseizures. Recently, sexual abuse has been suggested as a possible cause for this increased prevalence in women. It has, however, not been very clear if women have a different phenomenology of these type of seizures from men. In the present study, patients' cases as published in the literature are analysed in a detailed way, using a working classification by Betts et al to look for gender-specificity. Of the 62 cases, 76% concern women and 24% men; a percentage comparable to those published elsewhere. Ages range from 14 to 77 years-of-age, but 89% of patients are younger than 40. Sexual abuse was proven in 18 cases, all women. The phenomenology of the attacks was divided into tonic-clonic type and complex partial type of attack, or a combination of the two. Also, special types of attacks (swoons, tantrums, abreactive attacks and forthright simulation) were looked for. Males tended to suffer especially from tonic-clonic type seizures (80% of cases), while in women as many tonic-clonic type as complex partial type attacks were observed. Special types of attacks were observed at the same frequency in both sexes. The group of sexual abuse victims did not differ from the total group of women in this respect. The clinically more impressive nature of a tonic-clonic-type attack, that is more easily suspected to be 'real', might make this type of seizure a more male form of acting out. A prospective study on the incidence and phenomenology of pseudo-epileptic seizures in the general population is suggested to answer the new questions raised in this survey.


Subject(s)
Epilepsy/psychology , Seizures/psychology , Abreaction , Adolescent , Adult , Aged , Child , Child Abuse, Sexual/diagnosis , Child Abuse, Sexual/psychology , Epilepsy/diagnosis , Epilepsy, Tonic-Clonic/diagnosis , Epilepsy, Tonic-Clonic/psychology , Female , Humans , Male , Middle Aged , Risk Factors , Seizures/diagnosis , Sex Factors
5.
J Vasc Res ; 33(1): 47-52, 1996.
Article in English | MEDLINE | ID: mdl-8603126

ABSTRACT

In a previous study we have shown that the wall of the elastic carotid artery bifurcation (CAB) stiffens inhomogeneously with increasing age, the carotid artery bulb being most affected. In the present study the effect of ageing on the elastic properties of the wall and the strain the wall is exposed to along the muscular femoral artery bifurcation (FAB) was investigated using the CAB for comparison. The study was performed with 10 young (aged 20-30 years) and 10 old (50-60 years) presumed healthy volunteers. Distensibility along the bifurcation was determined by measuring noninvasively the maximum relative diameter changes of the artery during systole (peak delta d/d.100%), which is also a measure of strain, at various sites along both bifurcations by means of a vessel wall moving detector system. This system also makes the assessment of (end-diastolic) diameter possible. At all levels along the CAB, the diameter was significantly larger in the old than in the young. In the FAB, the diameter was only significantly larger in the old than in the young in the common and superficial femoral arteries. At all levels in the CAB, peak delta d/d.100% was significantly lower in the old than in the young, the carotid artery bulb being more affected than the common carotid artery (CCA), while in the FAB this parameter was lower in the old than in the young only in the common femoral artery (CFA). Peak delta d/d.100% was similar in the CCA and in the bulb in the young, but significantly higher in the CCA than at all levels in the bulb in the old. In the FAB, in the young peak delta d/d 100% was significantly higher in the CFA than at both levels in the deep and superficial femoral arteries, while in the old no significant differences in peak delta d/d.100% along the FAB could be detected. These findings indicate that the loss of wall elasticity with increasing age is different in the muscular and elastic arterial bifurcations investigated. The homogeneous distribution of wall elasticity in the elastic CAB at a younger age becomes inhomogeneous at an older age, while the opposite is observed in the muscular FAB. The changes in strain the different parts of the bifurcations are exposed to with increasing age are different in the CAB and the FAB. Differences in distensibility along bifurcations will make them deform inhomogeneously during the cardiac cycle.


Subject(s)
Aging , Cerebral Arterial Diseases/pathology , Muscle, Smooth, Vascular/pathology , Vascular Diseases/pathology , Adult , Biomechanical Phenomena , Blood Pressure , Cerebral Arterial Diseases/physiopathology , Elasticity , Femoral Artery/pathology , Heart Rate , Humans , Male , Middle Aged , Muscle, Smooth, Vascular/physiopathology , Vascular Diseases/physiopathology
6.
Cardiovasc Res ; 28(5): 610-4, 1994 May.
Article in English | MEDLINE | ID: mdl-8025904

ABSTRACT

OBJECTIVE: Arterial distensibility (DC) and compliance (CC) are vessel wall properties of large arteries that can be measured non-invasively with a custom made vessel wall movement detector system (VWMDS). This study investigated the reproducibility of this device in 10 volunteers. METHODS: To investigate intraobserver intrasession and intraobserver intersession variability, arterial diameter (D) and relative change in diameter during the heart cycle (delta D/D) were measured in the elastic common carotid artery, and in the muscular femoral and brachial arteries. Interobserver intrasession variability was examined in common carotid artery by two observers, while interobserver variability on the same image was assessed for common carotid and femoral arteries. Variability was expressed as the coefficient of variation. RESULTS: For common carotid artery, intraobserver intrasession variability was 7.9(SEM 1.6)% (delta D/D), 4.5(1.1)% (D), 8.3(1.3)% (DC), and 9.1(2.6)% (CC), respectively. In femoral artery it was 12.4(2.2)% (delta D/D), 2.7(0.6)% (DC), 13.4(2.2)% (DC), and 12.5(2.1)% (CC). For brachial artery it was 13.4(2.8)% (delta D/D), 2.5(0.5)% (D), 16.1(2.5)% (DC), and 15.6(2.6)% (CC). Intraobserver intersession variability was comparable to intraobserver intrasession variability for all vessels. Interobserver intrasession variability for common carotid artery was 11.3(2.6)% (delta D/D) and 8.6(1.9)% (D), but was larger for DC and CC. Interobserver variability on the same image was < 5% for common carotid and femoral arteries. CONCLUSIONS: In conclusion, the vessel wall movement detector system has a good technical reproducibility. Intraobserver intrasession and intersession variability are comparable, and are larger in muscular arteries. This might be due to a larger variation in tone of these arteries, which are under permanent neurohumoral control. Interobserver intrasession variability was larger than intraobserver variability and might be influenced by differences in observers' skill and spontaneous variation in vessel wall properties.


Subject(s)
Arteries/physiology , Radio Waves , Vasoconstriction/physiology , Adolescent , Adult , Brachial Artery/diagnostic imaging , Brachial Artery/physiology , Carotid Artery, Common/diagnostic imaging , Carotid Artery, Common/physiology , Compliance , Female , Femoral Artery/diagnostic imaging , Femoral Artery/physiology , Humans , Male , Middle Aged , Observer Variation , Reproducibility of Results , Ultrasonography
7.
J Hypertens ; 11(2): 171-6, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8385177

ABSTRACT

OBJECTIVES: It has been suggested that arteries age more quickly in borderline hypertensives (BHT) than in normotensives. If this hypothesis is correct, the decrease in distensibility and compliance in the carotid artery bifurcation should be most pronounced in the carotid artery bulb, because this site is known to be the most affected by age. DESIGN: Arterial distensibility was measured non-invasively by means of an ultrasound vessel wall moving-detector system at various sites along the carotid artery bifurcation in BHT and normotensive controls. METHODS: Sixteen bifurcations of male BHT (mean age 38 years) and 15 bifurcations of normotensive age-matched controls (NTO) were studied in subjects from a population study on borderline hypertension. To evaluate age-related changes, 18 bifurcations of normotensive young male subjects (NTY; mean age 24 years) were included in the study. RESULTS: In NTY subjects no significant variations in distensibility were found along the carotid artery bifurcation, but in NTO subjects the proximal and distal parts of the carotid artery bulb were significantly less distensible than the common carotid artery. In BHT the distensibility was significantly lower at all levels in the bulb than in the common carotid artery, and its proximal part was significantly stiffer than the rest of the bulb. CONCLUSIONS: The findings in this study indicate faster ageing of the carotid artery bifurcation in male BHT than in normotensives of comparable age. In particular, the proximal part of the carotid artery bulb, where the baroreceptors are predominantly located, is most affected by the disease.


Subject(s)
Aging/physiology , Carotid Arteries/diagnostic imaging , Carotid Sinus/diagnostic imaging , Hypertension/physiopathology , Adult , Carotid Arteries/physiology , Carotid Sinus/physiology , Humans , Hypertension/diagnostic imaging , Male , Pressoreceptors/physiology , Ultrasonography , Vascular Resistance/physiology
8.
J Hypertens Suppl ; 10(6): S35-9, 1992 Aug.
Article in English | MEDLINE | ID: mdl-1432323

ABSTRACT

AIM: To determine whether there are inhomogeneities in arterial wall distensibility with age and hypertension. BACKGROUND: It has been known for some years that arteries lose their elasticity with increasing age and that they are less distensible in subjects with established and borderline hypertension than in age-matched controls. RESULTS OF DATA ANALYSIS: In the carotid artery changes in arterial wall properties are not homogeneously distributed along the bifurcation. Both in older subjects and in those with borderline hypertension the loss of distensibility is most pronounced in the carotid artery bulb, while in borderline hypertensives the proximal part of the bulb, where the baroreceptors are predominantly located, is more affected than other parts of the bulb. The loss of distensibility in the bulb may explain the diminished baroreceptor sensitivity observed in older subjects. The pronounced involvement of the proximal part of the bulb in the decreased distensibility in borderline hypertensives suggests that local stiffening, probably leading to disturbed baroreceptor sensitivity, may contribute to the development of hypertension in these patients. The pattern of inhomogeneities in wall distensibility in borderline hypertensives at a relatively young age (average 38 years) is similar to that seen in older normotensive subjects (average age 57 years), supporting the idea that arteries age faster in hypertensives than in normotensives. CONCLUSION: In management of the borderline hypertensive patient, consideration should be given to preventing early ageing of the arterial wall rather than following arterial blood pressure.


Subject(s)
Aging/physiology , Carotid Arteries/physiology , Hypertension/physiopathology , Adult , Arteriosclerosis/physiopathology , Blood Pressure/physiology , Carotid Arteries/diagnostic imaging , Carotid Arteries/physiopathology , Carotid Artery Diseases/physiopathology , Compliance , Elasticity , Humans , Middle Aged , Ultrasonography
10.
Arch Mal Coeur Vaiss ; 84 Spec No 3: 95-6, 1991 Sep.
Article in English | MEDLINE | ID: mdl-1953292

ABSTRACT

The compliance of large arteries (for instance the carotid and femoral artery) can be non-invasively assessed with a vessel wall moving detector system, based upon phase tracking of the radio frequency signals generated by the arterial wall. A good compliance enables large arteries to manage the systolic flow jet from the heart more adequately, and has been suggested to protect these vessels from atherosclerosis. Arterial compliance has been found to be diminished in hypertensive subjects, even at an early stage of the disease. Antihypertensive treatment might restore compliance, depending on the drugs used. More recently, local stiffening of vessels and inhomogeneities in local distensibility have been observed in the carotid artery bifurcation of borderline hypertensives, and the time-dependent variation in local distensibility and compliance has been studied.


Subject(s)
Arteries/physiology , Blood Pressure , Carotid Arteries , Compliance , Female , Femoral Artery , Humans , Hypertension/physiopathology , Male , Oscillometry/methods
11.
Basic Res Cardiol ; 86 Suppl 1: 91-5, 1991.
Article in English | MEDLINE | ID: mdl-2036097

ABSTRACT

Atherosclerosis is an important cause of cardiovascular morbidity and mortality. A good arterial compliance has been suggested to protect large vessels from atherosclerosis. Arterial compliance is diminished in patients with essential hypertension. The influence of verapamil (calcium-antagonist) and nebivolol (beta-adrenoceptor antagonist) on the vessel-wall properties of the common carotid artery were investigated. The two drugs improved compliance of the common carotid artery. Results from other studies on arterial compliance and antihypertensive drugs are also discussed.


Subject(s)
Antihypertensive Agents/pharmacology , Arteries/drug effects , Adult , Aged , Arteries/physiopathology , Arteriosclerosis/prevention & control , Benzopyrans/pharmacology , Carotid Arteries/drug effects , Carotid Arteries/physiopathology , Ethanolamines/pharmacology , Female , Humans , Hypertension/drug therapy , Hypertension/physiopathology , Male , Middle Aged , Nebivolol , Vascular Resistance/drug effects , Verapamil/pharmacology
12.
J Cardiovasc Pharmacol ; 15(1): 109-13, 1990 Jan.
Article in English | MEDLINE | ID: mdl-1688966

ABSTRACT

The effect of chronic administration of verapamil, following a double-blind, crossover protocol, on the distensibility and cross-sectional compliance of the common carotid artery was investigated in 19 patients with essential hypertension. Distensibility was significantly increased during verapamil treatment as compared to placebo for both left and right common carotid artery (p less than 0.01 and p less than 0.05, respectively). The cross-sectional compliance was significantly increased during verapamil treatment for the right common carotid artery (p less than 0.05). For the left common carotid artery, the difference did not reach the level of significance (p = 0.16). The common carotid artery diameter and the arterial pulse pressure were not significantly different during verapamil treatment as compared with placebo. The results of this study indicate that chronic treatment with verapamil increases distensibility and cross-sectional compliance of the common carotid artery in hypertensive subjects. These improvements have to be considered as changes in arterial wall properties because no significant differences in pulse pressure and diameter could be detected between the verapamil and placebo periods. Improved arterial wall properties could result in a better management of the flow jet from the heart, and might protect the patients from atherosclerotic complications of hypertension.


Subject(s)
Carotid Arteries/physiopathology , Hypertension/drug therapy , Verapamil/pharmacology , Adult , Aged , Blood Pressure/drug effects , Double-Blind Method , Female , Humans , Hypertension/physiopathology , Male , Middle Aged , Muscle, Smooth, Vascular/drug effects , Randomized Controlled Trials as Topic , Ultrasonics
13.
J Hypertens Suppl ; 7(6): S262-3, 1989 Dec.
Article in English | MEDLINE | ID: mdl-2576665

ABSTRACT

The effects of verapamil (a calcium antagonist) and nebivolol (a novel, selective beta 1-adrenoceptor blocker) on carotid artery distensibility and cross-sectional compliance were studied non-invasively in hypertensive patients with the use of a high-resolution multigate pulsed Doppler system. Arm blood pressure measurements were made with an automated device (Dinamap). After a 4-week washout period, 19 patients (aged 21-73 years) with essential hypertension entered a double-blind randomized placebo-controlled crossover study with 120 mg verapamil or placebo three times a day for 4 weeks. After the administration of verapamil, carotid artery distensibility and cross-sectional compliance were significantly larger (P less than 0.05) than after placebo. Using the same protocol, 29 patients (aged 25-70 years) were given 5 mg nebivolol or placebo once a day for 4 weeks. After the administration of nebivolol, carotid artery distensibility and cross-sectional compliance were significantly larger (P less than 0.05) than after placebo. In both studies no significant differences in diameter and pulse pressure were found between placebo and verapamil or nebivolol. Blood pressure was decreased similarly with both verapamil and nebivolol. These results indicate that both verapamil and nebivolol favourably influence carotid artery distensibility and cross-sectional compliance of the common carotid artery, resulting in a better management of the systolic pressure pulse. The improved carotid artery distensibility may help to protect the patient against atherosclerotic complications of hypertension.


Subject(s)
Adrenergic beta-Antagonists/therapeutic use , Antihypertensive Agents/therapeutic use , Benzopyrans/therapeutic use , Carotid Arteries/drug effects , Ethanolamines/therapeutic use , Hypertension/drug therapy , Vascular Resistance/drug effects , Verapamil/therapeutic use , Adult , Aged , Carotid Arteries/physiopathology , Double-Blind Method , Female , Humans , Hypertension/physiopathology , Male , Middle Aged , Nebivolol , Randomized Controlled Trials as Topic , Vascular Resistance/physiology
14.
Stroke ; 20(10): 1336-40, 1989 Oct.
Article in English | MEDLINE | ID: mdl-2678613

ABSTRACT

In a prospective study using a multigate pulsed Doppler system, minor (less than 30% diameter reduction) carotid artery lesions were diagnosed by detecting not only abnormalities in the blood flow pattern, but also local changes in artery wall distensibility. For the diagnosis of more severe lesions, additional information was obtained from disturbances in the Doppler audio spectrum. Biplane arteriography was used as a reference. The observed agreement, sensitivity, and specificity were 86.6%, 90.3%, and 88.6%, respectively, for all lesions and 85.7%, 82.1%, and 88.6%, respectively, when only minor lesions were considered. kappa (a chance-corrected measure of agreement) was 81.7%. If only blood flow abnormalities were used to detect minor lesions, 43.5% would be missed. Our results indicate that minor carotid artery lesions can be diagnosed noninvasively more accurately when both local blood flow irregularities and local changes in vessel wall distensibility are taken into account.


Subject(s)
Carotid Artery Diseases/diagnosis , Intracranial Arteriosclerosis/diagnosis , Ultrasonography , Adult , Blood Flow Velocity , Cerebrovascular Circulation , Humans , Middle Aged , Prospective Studies , Vascular Resistance
15.
Pediatr Res ; 25(1): 94-6, 1989 Jan.
Article in English | MEDLINE | ID: mdl-2919123

ABSTRACT

The vessel wall properties of the common carotid artery were noninvasively studied in 53 normotensive, presumed normal boys of various ages (4-19 yr) with the use of a multigate pulsed Doppler system. This device allows the on-line recording of velocity profiles and the relative changes in carotid artery diameter during the cardiac cycle. From the width of these profiles, the internal diameter of the carotid artery can be determined. With the use of internal carotid artery diameter, relative changes in carotid artery diameter during the cardiac cycle, and pulse pressure the pulse pressure, as measured in the brachial artery, the distensibility coefficient and the cross-sectional compliance were calculated. The children were allotted to three different age groups: group I (4-10 yr), group II (11-14 yr), and group III (15-19 yr). In the older children (group III) the systolic arterial pressure and the pulse pressure were significantly higher than in groups I and II. The carotid artery diameter was significantly larger and the distensibility coefficient was significantly smaller in group III than in groups I and II. The cross-sectional compliance was not significantly different in the age groups, which can be explained by the larger artery diameter in the older age group. The findings indicate that the carotid artery wall is less distensible in adolescents than in younger children. The subjects in group III showed similar carotid artery wall properties as the young adults (aged 20-34 yr) in a previous study. Therefore, it is likely that in adolescents the vascular system can be considered as mature as far as the arterial wall properties are concerned.


Subject(s)
Carotid Arteries/physiology , Ultrasonics , Adolescent , Age Factors , Blood Pressure , Carotid Arteries/anatomy & histology , Child , Child, Preschool , Humans , Male , Mathematics , Pulse
16.
Ultrasound Med Biol ; 14(7): 563-9, 1988.
Article in English | MEDLINE | ID: mdl-3059645

ABSTRACT

The vessel wall properties of the common carotid artery were studied noninvasively in normotensive and borderline hypertensive male volunteers of various ages with the use of a multi-gate pulsed Doppler system. In the younger age group (20-35 y) both distensibility and cross-sectional compliance were significantly less in the borderline hypertensive group. In the older borderline hypertensive subjects (50-69 y) distensibility (p less than 0.05) and cross-sectional compliance (p = 0.06) were also less than in the control subjects. The reduced distensibility and cross-sectional compliance likely result from a decrease in arterial wall elasticity because the relative increase in common carotid artery diameter during systole is diminished in borderline hypertensives, despite the fact that their pulse pressure is similar to or higher than that in control subjects. The less pronounced differences in vessel wall properties between borderline hypertensive and normotensive volunteers in the older age group may be a consequence of the changes in these properties with age, partly masking the alterations due to borderline hypertension. Since the stiffer behavior of the common carotid artery in borderline hypertensives is associated with relatively slight changes in blood pressure, the question can be raised whether the alterations in arterial wall properties are really a result of the elevated arterial blood pressure; these alterations might develop independent of the blood pressure elevation.


Subject(s)
Carotid Arteries/anatomy & histology , Hypertension/pathology , Ultrasonography , Adult , Aged , Aging , Blood Pressure , Blood Volume , Carotid Arteries/physiology , Elasticity , Humans , Hypertension/physiopathology , Male , Middle Aged , Systole , Ultrasonography/methods
17.
Ultrasound Med Biol ; 14(7): 571-4, 1988.
Article in English | MEDLINE | ID: mdl-3059646

ABSTRACT

The vessel wall properties of the common carotid artery were noninvasively studied in 109 normotensive, presumed normal male and female volunteers of various ages (20-69 y) with the use of a multi-gate pulsed Doppler system. This system allows the on-line recording of velocity profiles and the relative changes in carotid artery diameter during the cardiac cycle (delta d/d). From the width of these profiles the systolic internal diameter (d) of the carotid artery can be determined. With the use of d, the maximal increase in delta d/d during systole and the pulse pressure, as measured in the brachial artery (delta p), the distensibility coefficient and the cross-sectional compliance were calculated. Both distensibility and cross-sectional compliance were significantly lower in females than in males, irrespective of age. This likely results from a stiffer arterial wall behavior in females, because the relative increase in vessel diameter during the cardiac cycle is lower in females than in males, despite the fact that their pulse pressure values are not significantly different. The carotid artery diameters were similar in men and women. The findings in the present study indicate that the common carotid artery is stiffer in females than in males of comparable age. Therefore, sex-dependent differences have to be considered in the interpretation of arterial distensibility and cross-sectional compliance.


Subject(s)
Carotid Arteries/anatomy & histology , Ultrasonography , Adult , Aged , Blood Flow Velocity , Blood Pressure , Elasticity , Female , Heart Rate , Humans , Male , Middle Aged , Myocardial Contraction , Sex Factors , Ultrasonography/methods
18.
Ultrasound Med Biol ; 14(6): 459-64, 1988.
Article in English | MEDLINE | ID: mdl-3067428

ABSTRACT

The diagnostic accuracy of noninvasive detection of carotid artery lesions with a diameter of less than 50% (minor to moderate) and greater than 50% reduction (severe) with the use of a multi-gate pulsed Doppler system (spectral analysis combined with the detection of flow disturbances) was studied in patients with focal neurological symptoms. Biplane arteriography was used as a reference. For all lesions the diagnostic accuracy (observed agreement), sensitivity and specificity was 88, 92, and 84%, respectively, and 84, 83, and 84%, respectively, when only minor to moderate lesions were considered. Kappa, a chance-corrected measure of agreement, which takes into account the marginal distribution of the data and, hence, may be considered to be a better parameter to describe diagnostic accuracy, was found to be 82.2%. The results in this study compare favorably with those obtained in studies employing duplex techniques (B-mode image combined with single-gate pulsed Doppler) and indicate that minor to moderate carotid artery lesions are detected rather accurately with the use of a multi-gate pulsed Doppler system.


Subject(s)
Arteriosclerosis/diagnosis , Carotid Artery Diseases/diagnosis , Spectrum Analysis , Ultrasonography , Arteriosclerosis/diagnostic imaging , Carotid Arteries/diagnostic imaging , Carotid Artery Diseases/diagnostic imaging , Humans , Prospective Studies , Radiography , Sensitivity and Specificity
19.
Ultrasound Med Biol ; 12(6): 465-71, 1986 Jun.
Article in English | MEDLINE | ID: mdl-3523921

ABSTRACT

Changes in distensibility and cross-sectional compliance of the common carotid artery with age were studied in 80 presumed healthy volunteers, varying in age between 20 and 69 y. The distensibility was assessed from the relative increase in arterial diameter during systole normalized with respect to the arterial pulse pressure. The cross-sectional compliance was obtained by multiplying the distensibility by the arterial diameter. The relative diameter changes of the common carotid artery during the cardiac cycle were recorded on-line with a high resolution multigate pulsed Doppler system. The arterial diameter was assessed from the width of the velocity profiles which can also be recorded on-line with this system. Arterial pulse pressure was determined from brachial artery cuff blood pressure measurements. Both distensibility and cross-sectional compliance of the common carotid artery decreased linearly with age, starting in the third age decade. The reduction in the latter parameter was less pronounced, probably as a consequence of an increase in arterial diameter with age.


Subject(s)
Aging , Carotid Arteries/anatomy & histology , Ultrasonography , Adult , Aged , Blood Pressure , Elasticity , Humans , Male , Middle Aged , Pulse
SELECTION OF CITATIONS
SEARCH DETAIL
...